document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1018570>Question 1018570</A>: <I><SPAN STYLE=\"word-break: break-all;\"> sec(-7pi/12)<BR>\n" );
document.write( "using difference and sum identities </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #634663 by </B><A HREF=/tutors/aboutme.mpl?userid=stanbon><B>stanbon(75887)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=stanbon><IMG SRC=http://www.algebra.com/images/aboutme-small.gif BORDER=0 alt=\"About Me\" VALIGN=MIDDLE></A>&nbsp;<IMG SRC=http://www.algebra.com/images/nopicture.jpg><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=634663\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\">  sec(-7pi/12)<BR>\n" );
document.write( "using difference and sum identities <BR>\n" );
document.write( "----<BR>\n" );
document.write( "sec(-7pi/12) = 1/[cos(-7pi/12)]<BR>\n" );
document.write( "=====<BR>\n" );
document.write( "= 1/[cos(-3pi/12)-4pi/12]<BR>\n" );
document.write( "-----<BR>\n" );
document.write( "= 1/[cos(-pi/4 +(-pi/3))]<BR>\n" );
document.write( "-----<BR>\n" );
document.write( "= 1/[cos(-pi/4)*cos(-pi/3) - sin(-pi/4)*sin(-pi/3)]<BR>\n" );
document.write( "-----<BR>\n" );
document.write( "= 1/[(sqrt(2)/2)(1/2) - (-sqrt(2)/2)(-sqrt(3)/2))<BR>\n" );
document.write( "-----<BR>\n" );
document.write( "= 1/[(sqrt(2)/4) - (sqrt(6))/4]<BR>\n" );
document.write( "----<BR>\n" );
document.write( "= 4/[sqrt(2)-sqrt(6)]<BR>\n" );
document.write( "-----------------------------<BR>\n" );
document.write( "Cheers,<BR>\n" );
document.write( "Stan H.<BR>\n" );
document.write( "------------ </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );